Improvement in the manufacture of planished sheet-iron



UNITED STATES PATENT QFFIGE.

W. DEWEES WOOD, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN THE MANUFACTURE OF PLANISHED SHEET-IRON.

Specification forming part of Letters Patent No. 172,235, dated January 11, 1876; application filed December 14, 1875.

To all whom it may concern:

Be it known that I, W. DEWEES WOOD, of Pittsburg, county of Allegheny, State of Pennsylvania,have invented or discovered a new and useful Improvement in Manufacture of Planished Sheet-Iron; and I do hereby declare the following to be a full, clear, concise, and exact description thereof.

My present invention relates to an improvement in the manufacture of What is known in the trade as planished sheet-iron.

In a patent granted to me May 14, 1861, the use in a manner therein described of carbonaceous matter ground in oil is set forth as then a new improvement in the art; and this also constitutes a step in the process described and claimed in thepatentgranted to meJulyl, 1873, reissue No.5,474. In both of these patcuts the coating or Wash of such compoundis represented as being applied independently of a baking process before finishing in rolls, or by hammers. I have ascertained by experiment that if such coating or wash be applied to the faces of the sheets, and thoroughly baked thereon before finishing in rolls or hammers, a sheet is produced much superior in its finish to any heretofore put on the market, and, on account of the perfectness of its glaze, much less liable to injury by oxidation, and, consequently, so much the more durable.

In carrying out my improvement the bar or billet is subjected to the operation of breaking down, by the use of' rolls of any suitable construction, till it .comes to about Nos. 20 to 22 Wire-gage. I then, after removing the surface oxides as completely as may be desirable or practicable, by scaling, or in other suitable way known in the art, coat or wash the sheets (preferably on both sides) baked into or onto the surfaces of the sheets, I so as, by some chemical or mechanical action not fully understood, except by its results, the sheets will have the capacity, when again brought up to the proper temperature-say, a low red heat-for being finished by rolling. or hammering, or both, of reciving a better finish, a more perfect glaze, with less liability to rust than has yet been attained by known processes. While the baking operation is going on other suitable means or material may be employed to protect the sheets against injurious oxidation.

I claim herein as my invention- As a step in the manufacture of planished sheet-iron baking a mixture of carbonaceous matter and oil or other hydrocarbon into or onto a previously-deoxidized or sealed surface of the sheet While inclosed or protected against injurious reoxidation, and preparatory to finishing in rolls, or hammers, or both, substantially as set forth.

In testimony whereof I have hereunto set' my hand.

W. DEWEES WOOD.

Witnesses: V 7

JAMES M. OHRIs'rY, GEORGE H. GHRIsTY.

In this manner the mixture speci- 

